Graunching noise when depressing clutch pedal

[DennisR]

Bearing in mind I have done no work on the engine or transmission other than new timing gear and an oil change, I start it up regularly whilst I`ve been repainting etc., today whilst I was sat in it, listening to the sound of music (it was running) for some reason I went to push the clutch in and had only just moved the pedal and there was a sound like when you try to engage gear out of sync. Not had it before, I know it`s like `how long is a piece of string` but any thoughts on what it could be ?
Just one thing, while I was having trouble starting it recently on one occasion I thought the starter had stayed engaged, it cleared by itself and it didn`t happen again so thought no more of it.

[SeaSlugs]

Hmm try this:

Start the engine with trans in neutral NOT depressing the clutch pedal.

lightly depress the clutch pedal, just enough to start feeling resistance - if everything is in spec and adjusted correctly the throw-out bearing should just start to touch the fingers and spin. If you need to remove the inspection cover and watch the bearing move and just start to touch. If you hear your weird noise my guess is the throw-out bearing is shot. usually they chirp, squeal, or sound like someone rolling a oil drum on concrete and growl.

Now if its fully depressed and you hear a grinding or "dragging" noise check to make sure your starter bolts aren't too long and dragging the back of the flywheel as pressing the clutch moves the whole crankshaft forwards.

If it sounds like ball bearings in a blender you may have broken a starter bendix bolt and its flying around the housing. (which you may find out sooner or later if you cant get the starter to turn the engine over)

[DennisR]

I did start in neutral, but the sound started almost as soon as I touched the pedal, I thought I`d let it cool down and pull the starter as a first step, I didn`t like the idea of fully depressing the pedal in case I do more damage.

[SeaSlugs]

yea which leads me to either your throwout bearing siezed as it is not in contact unless the pedal is pressed, OR your starter bolts could be too long and the clutch action shoves the crank forward and hits the bolts. Take the bolts out and inspect the ends - will be obvious if they have been rubbing.

or like i said since you mentioned starter issues you could have busted a bolt off it and got hit by the ring gear when it moved forward a hair from the clutch...

[C26Pinelake]

Graunch seems to be an inappropriate word. Please use a more descriptive word that everyone can understand. Wayne

[harryc]

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I had that develop years ago. I pulled the inspection plate and greased the bearing and it worked fine.

[billwill]

Youve got a trobeaing tahas harden grease.

[Larry Jenkins]

Originally Posted by billwill

Youve got a trobeaing tahas harden grease.

Same to you, fella..

[Dino's A]

Originally Posted by harryc

I had that develop years ago. I pulled the inspection plate and greased the bearing and it worked fine.

How did you grease the throwout bearing? That grease fitting you pumped grease into was only to lube the collar.

[harryc]

Sometimes enough grease will work its' way up into the bearing to stop any noise---especially if it's the original bearing--I've done it several times

[Tom Wesenberg]

Originally Posted by Dino's A

How did you grease the throwout bearing? That grease fitting you pumped grease into was only to lube the collar.

Yep, as Harry said it will grease the bearing, at least if it's an original bearing.

[Patrick L.]

I tend to agree with the release bearing also, but, another possibility could be the pedal rubbing against the floor board shield or a really dry shaft bushing.

[Marshall V. Daut]

I am jumping on the dogpile and going with the throwout bearing as the #1 suspect. As already suggested, take out the floor boards, remove the inspection cover on the bellhousing above the clutch, and while the engine is running, push in the clutch pedal. You should very plainly be able to hear loud scraping noises if the throwout bearing is at fault. If so, the rear end and transmission need to be removed so that the throwout bearing can be replaced. Do NOT use an Aetna brand, which is made in Mexico and will fail rapidly. Doing this from the rear is far quicker and easier than pulling the engine and struggling to get it back into place.
Also, this is beginning to sound like a broken record on my part, but when I hear of such noises anymore, I also consider the flywheel ring gear beginning to "walk" forward and scraping against the flywheel housing re-inforcing ribs. This happens because years ago, cheapie flywheel ring gears from off-shore were made that were slightly too large. They get pulled forward after use by the Bendix drive constantly slamming against it when starting the engine. You can either continue driving the car to see if the scraping noise turns to banging as the gear walks forward on the flywheel, or remove the starter and examine the ring gear to ensure that it is up against the ledge on the flywheel. NO GAP should exist between the two! If you can put any size feeler gauge between the ring gear and the ledge behind it, that's the source of your problem. It will only get worse. This happens because the crankshaft develops aft-to-rear movement as the thrust Babbitt on the rear main cap wears away, allowing the crank to move forward when the clutch pedal is depressed. If the ring gear is beginning to move forward, this will at first cause a scraping noise, which will shortly develop into a banging noise as the ring gear moves forward more and begins striking instead of scraping against the inside of the flywheel housing. This can be repaired by driving the ring gear back into place around the full 360 degree arc of travel. If the gear walks again in the future, you'll need to stake it in place at 180 degree spacing (to maintain balance) with threaded Allen head set screws.
But, the most likely cause of your scraping is a bad throwout bearing, as suggested by the Peanut Gallery so far. .
Marshall

[DennisR]

Thanks for all the replies, yes it would appear to be the bearing. I did as suggested and pumped some grease into the nipple, the noise reduced at first and now has almost gone.
I guess I should be looking at getting a clutch assembly organised for the not to distant future.
Now there looms another dilemma, engine or rear end removal, I`ve looked at all the posts on the merits of both methods, and I don`t know which way to go. I must admit the rear end seems the best way, but, the dreaded spring scares the hell out of me. I don`t have a garage, I work in the open on my drive, I have built a temp. shelter for the spray job, I know it would mean possible damage to my new paintwork but engine cranes are quite reasonable and at least I can be sure, as sure as you can be, of reaching my next birthday, 73, in one piece

[1931 flamingo]

Spring does not have to be removed to drop the rear end.
Unbolt everything, REMOVE the wheels and drop the rearend down and back. If still hesitant, after the rear is dropped, wrap a chain around the spring.
Just because the t,out brg was making noise does NOT mean clutch needs to be replaced. Adj it and drive it. JMO
Paul in CT

[Marshall V. Daut]

Get a large "C" clamp and as soon as the rear end has been dropped via a floor jack to clear the rear cross member, install the clamp near the spring's center bolt. That will eliminate the possibility of a rusted center bolt snapping while the rear end is down. Also, don't pull the rear end completely out from underneath the car. Pull it back only enough to clear the brake cross shaft. That way, if for some unfathomable reason the center bolt and the clamp fail (HIGHLY unlikely!), the spring leaves can only jump up so far before they contact the rear bumper braces. But, don't worry. That won't happen.
The rear end removal is the far better way to change the throwout bearing versus engine removal. I can drop the rear end and pull the bellhousing w/transmission in about an hour. I'd still be unhooking and disconnecting stuff from the engine prior to pulling it in that amount of time. And removing the engine is MUCH easier than trying to shove it back in and re-connect everything.
Marshall

[DennisR]

Appreciate the replies, wasn`t intending to replace the bearing yet, just anticipating a future clutch renewal, if the bearing is on the way out I would do the whole thing when the time comes.